<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>transform</title>
  <style>
    /* .box {
      width: 200px;
      height: 200px;
      background: red;
      margin: 50px auto;
      transform: rotate(30deg);
      transition: 1s all ease;
    }

    .box:active {
      transform: rotate(0);
    }

    .box1 {
      width: 200px;
      height: 200px;
      background: green;
      margin: 50px auto;
      transform: skew(0);
      transition: 1s all ease;
    }

    .box1:active {
      transform: skew(45deg, 30deg)
    } */
    @keyframes moveBox {
      0% {
        width: 200px;
        height: 200px;
        font-size: 14px;
        background-color: #ccc;
      }

      25% {
        width: 400px;
        height: 200px;
        font-size: 14px;
        background-color: #ccc;
      }

      50% {
        width: 400px;
        height: 400px;
        font-size: 14px;
        background-color: #ccc;
      }

      75% {
        width: 400px;
        height: 400px;
        font-size: 30px;
        background-color: #ccc;
      }

      100% {
        width: 400px;
        height: 400px;
        font-size: 30px;
        background-color: green;
      }
    }

    /* .box2 {
      width: 200px;
      height: 200px;
      background-color: #ccc;
      font-size: 14px;
      margin: 50px auto;
      animation-name: moveBox;
      animation-duration: 3s;
      animation-timing-function: ease;
      animation-iteration-count: infinite;
      animation-fill-mode: forwards;
      animation-direction: alternate;

    } */

    /* .box2:active {
      animation-play-state: paused;

    } */
    /* .active {
      animation-play-state: paused;
    } */


    .box3 {
      width: 300px;
      height: 300px;
      background-color: #ccc;
      font-size: 14px;
      margin: 50px auto;
      transform: rotateY(0);
      transition: 1s all ease;

    }

    .box3:active {
      transform: perspective(600px) rotateY(60deg);

    }
  </style>
</head>

<body>
  <!-- <div class="box">
    马上十二点了，好好学习，争取在19年下半年拿到30k的工资
  </div>
  <div class="box1">
    马上十二点了，好好学习，争取在19年下半年拿到30k的工资
  </div> -->
  <!-- <div class="box2" onclick="this.className='box2 active';">
    马上十二点了，好好学习，争取在19年下半年拿到30k的工资
  </div> -->
  <div class="box3">
    马上十二点了，好好学习，争取在19年下半年拿到30k的工资
  </div>
</body>

</html>